Public health officials said they were "really pleased" with the response from women who had received a letter offering tests.

I am getting married this year and this has just put a big black cloud over the weddingElaine Luther, Former patient

Two patients are known to have contracted the virus but Aneurin Bevan University Health Board - which covers the former Gwent area - said the risk of infection was low.

Hepatitis C is a virus which can lead to inflammation of the liver. If untreated, the infection can cause chronic liver disease and, very rarely, cancer of the liver.

Deborah Marsh, from Nelson in Caerphilly county, said she had a gut feeling she would receive a letter - which arrived on Friday morning.

The 43-year-old added: "I think it's awful and it makes you wonder what else is out there.

"You think through your mind how many times you've had to deal with the gynaecology department.

"I intend to have a blood test and I suppose it's going to be a very stressful time waiting for the result.

"Day-to-day life... is stressful and you don't need this to add to it."

Hepatitis C

Hepatitis C is a virus which can lead to inflammation of the liver

If untreated, the infection can cause chronic liver disease and, very rarely, cancer of the liver

Up to 1 person in 250 carries Hepatitis C but it does not automatically lead to health problems

It is transmitted through blood-to-blood contact and, very rarely, through sexual intercourse

The most common route of transmission in the UK is intravenous drug use

It cannot be transmitted through social contact, kissing or sharing food and drink

SOURCE: Aneurin Bevan University Health Board

The alert was raised after the health board, which covers the former Gwent area, learnt a retired obstetrics and gynaecology worker had tested positive for the illness.

The individual mainly worked at Caerphilly District Miners Hospital but also worked briefly at Wrexham Maelor Hospital and the old East Glamorgan Hospital near Pontypridd.

Patients at a number of hospitals around the UK in the 1970s and 1980s are also being contacted if they were treated by the worker.

Aneurin Bevan University Health Board has arranged a series of nurse-led clinics to test those in Wales who come forward.

The majority will be held at Ysbyty Ystrad Fawr in Ystrad Mynach and at the Royal Gwent Hospital.

The health board's public health director, Dr Gill Richardson, said: "We would encourage all women who receive a letter to contact the dedicated helpline number which is contained in each letter, to arrange their test as soon as possible.

"We need to again stress that the risk of transmission is low and testing is being provided as a precautionary measure."

People who have not received a letter but still have concerns are advised to contact NHS Direct on 0845 46 47 or contact their GP.